1. Field of the Invention
The present invention generally relates to a lens, in particular, to a microlens having magnifying function.
2. Description of Prior Art
Under the lead of a thriving technical industry, it is able to establish a substantially solid experience and technique for semiconductor in terms of design, simulation, process, packaging, and test, which have a significant advantage for developing MEMS (micro-electro-mechanical system) hereafter. Nowadays, the development of each electronic product has a trend in pursuing the goals of lightness, thinness, shortness, and smallness, so there is an amazing speed in changing the outlook of many electronic products, for example, the design of electronic hardware, computer or microprocessor.
To cope with the developing direction of electronic product in the designing trends of lightness, thinness, shortness, and smallness, the size of each electronic element is continuously microminiaturized. So far, the size of electronic element has broken the limitation that may be directly observed by human naked eye, even a deep-submicron state having reached already.
Based upon the microminiaturizing development of element size, a totally different difficulty is further emerging on the integrating level of microstructure. Since element size is moved toward a standard beyond the level of deep-submicron, even aerosol particle easily ignored in the past will become a critical factor in today by influencing the element yield. Later on, in order to promote the element yield, clean room is established to remove the influence of this impurity in the air, thereby the aforementioned influence being effectively improved and removed.
Although the establish of aforementioned clean room has removed the influence of the aerosol particle in the air to effectively promote element yield, however, the influence of yield not only comes from the impurity in air, but also originates from the process of facilities and elements themselves. In a clean room, each facility has its own usage lifetime, so before the usage lifetime it will be worn out to generate fissure, which easily releases micro-particle formed as dust that is unable to be observed by human naked eye. If dust invades element itself during process, for example, invading into a hole of a circuit board, then it is difficult to find out an occurrence of a defect during element integration. Furthermore, during a processing procedure of PCB (printed circuit board), a through hole on the PCB is acted as a pathway for an electric connection between copper foils arranged on two plate surfaces. Wherein, conductive metal is plated on the inner surface of the through hole, such that an electric connection is created between the copper foils arranged on the two plate surfaces. If it is impossible to connect the conductive metal plated on the internal surface of the through hole, then it will directly influence the electric connection between two plates of the PCB.
Currently, although micro-technique has developed into an observing dimension above nano-level because of the need of technology, a solution for above problem has not yet developed. In other words, a defect of an electronic product still can not be detected immediately following the movement of an inspector, which becomes a problem needed to be solved urgently by current electronic industry during the effort to pursue high yield and high efficiency.